Hmm. An idea regarding centered view, somewhat inspired by FVWM: maybe the distance from the edge that triggers view scrolling could be increased, to something greater than magical attack range? That would fix the major issue with centered view being impractical (i.e. monsters instakilling you from offscreen), without requiring (difficult) optimization of the SDL code.

It'd be a temporary workaround, not a long-term fix, but it would offer some reprieve from the major performance issues on the Win32 and SDL platforms.